Microsoft is in the final stages of deciding between two names for its search engine. The winner will be backed by a $US100 million brand campaign.

From leaked memos and employee blog posts, it seems Microsoft is now trialling a new-and-improved version of its search engine, Live.

While little known in these parts, or anywhere, Live is central to Microsoft’s plan to chase down Google’s huge lead in search, and search ads.

The company's ex-pat CFO, Chris Liddell is one who agrees that "Live" isn't working, telling the Seattle Tech Report: "We have to think about things like a new brand, and marketing that."

Now, Advertising Age says Microsoft will spend $US80 million to $100 million advertising its re-launched search engine.

But what should it be called. One contender is Kumo, which sounds unfortunately like a tire company, and about as exciting. It does seem to be more than a project code-name, too, as Microsoft has registered trademarks and URLs around it.

What could be worse than Kumo?

Bing.

Silicon Valley Insider reported over the weekend that Microsoft has trademarked the word, and taken over the domains bing.com and bing.net.

Bing. Hmmmn. It’s definitely go potential for attracting the under 12s.

A greater problem for Microsoft: explaining how Live, the search engine (as it’s called for now) and Live the other-bunch-of-services (now with a Facebook look) tie in with its commercial products.